

Almost all of the urban population in Europe remains exposed to PM2.5 concentrations higher than those indicated by the World Health Organization (WHO). This is 94% of city residents, who are mainly exposed to fine particulate matter, those with a diameter equal to or less than 2,5 µm. These particles are mainly emitted by the combustion of solid fuels for domestic heating, industrial activities and road transport. And they contribute, together with numerous other pollutants, to the (poor) state of the air quality in the cities and skies of Europe.
The Italy stands out negatively because it is among the countries that exhibit, in 2023 and 2024, concentrations above the limits identified in the EU. While from the WHO, in 2021, guidelines on global air quality on particulate matter (PM2.5 and PM10), ozone, nitrogen dioxide, sulphur dioxide and carbon monoxide with values lower than the European ones, with the aim of preventing the impact of air pollution on health.
The last relationship on the state of air quality in theEuropean Environment Agency (EEA) (1) provides the latest official data, covering the last two years, on the levels of key air pollutants in Europe, and compares these concentrations with current limits, with the EU 2030 standards and with more stringent WHO guidelines.
According to data collected at various monitoring stations in the EU, the standards were met for fine particulate matter (PM 2.5) (99% of stations) and nitrogen dioxide (NO2) (98% of stations), two significantly harmful air pollutants. Despite this, the limits are far from WHO guideline levels. And air pollution continues to represent the most significant environmental risk to health of the population, which is the basis of low quality of life, avoidable diseases and deaths.
I key messages of the report (2) highlight that, despite the general improvement, Air quality standards are not fully met all over Europe.
In particular "Since 2011, all countries have reduced urban population exposure to fine particulate matter PM2.5, the most harmful pollutant for health. However, the vast majority (94%) of the EU urban population remains exposed to PM2.5 concentrations above the level recommended by the World Health Organization, highlighting the need for additional measures to reduce the associated health risks".
The concentrations of CO2 In many places, they are already below the EU standards for 2030. At the same time, further measures will be needed to improve air quality, especially in cities.
According to the report, “Air quality in Europe has improved significantly in recent decades for most pollutants. For some pollutants, such as benzene e cadmium, European countries are already meeting the standards set by European Union legislation on air quality. Positive improvements can also be observed for other air pollutants, such as sulfur dioxide, carbon monoxide, lead, arsenic o nickel, with only a few monitoring stations in Europe showing values for these pollutants above EU standards. However, a significant number of locations in the EU show concentrations of other pollutants above the standards currently in force, as well as to the more stringent WHO guideline values".
The picture becomes clearer when looking at the percentage of monitoring stations that, in 2023, comply with the air quality guidelines. This percentage, which is high for compliance with the current limits for PM2.5, PM10, NO2 (nitrogen dioxide) and O3 (ozone), drops when looking at compliance with the future EU limits for 2030. In this case, the percentages drop at values between 59% of stations for the PM2.5 and 71% forozone.
When measured against the more stringent WHO guideline levels, the number of monitoring sites where air quality is considered safe for health was relatively low in 2023, particularly for PM 2,5 and ozone. The risk of health impacts from these pollutants includes respiratory and cardiovascular diseases. This data emerges precisely if we look at the percentages of monitoring stations that comply with the WHO guidelines. In the latter case, only 8% of monitoring sites for PM2.5 it is compliant and only the 2% as regards'ozone. Things are a little better for PM10 (36%) and nitrogen dioxide (30%).
The EEA explains that, “Although fuel combustion is a common source of most of these pollutants, reducing health risks often requires a combination of different measures due to the variation in the specific sources contributing to each pollutant. For example, for NO2 the main source is transportation, especially road traffic, and so NO2 tends to be a particular problem in urban areas".
Transport also causes emissions of PM 10 and PM 2.5 but these are also affected by the contribution of other economic activities and domestic combustion of solid fuels.
The Italy often exhibits critical data.
If you look at the levels of PM10, for example, it emerges that (with an average daily limit in the EU of 50 μg/m3) “Concentrations above the EU daily limit value for PM10 are mainly found in Italy and some Eastern European countries. In many Central and Eastern European countries, solid fuels such as coal and wood They are used for domestic heating and in some industrial plants and power plants. Po Valley, in northern Italy, is a densely populated and industrialized area with specific meteorological and geographical conditions that favor theaccumulation of air pollutants in the atmosphere. Some concentrations exceed the EU daily limit value also in the Canary Islands, mainly due to the natural contribution of Saharan dust".
For PM2.5, concentrations above the EU annual limit value are still present Italy, Together with Turkey and to the majority of countries in Western Balkans. Also for theozone in 2023 the highest concentrations were found in Eastern Mediterranean Seain Italy, in Iberian Peninsula and in 'central Europe.
The WHO global air quality guideline levels (3) were established in 2021. They are lower than the EU limit and target values and aim to prevent significant impacts of air pollution on human health.
Le WHO guidelines on air quality are not legally binding but represent a reference for countries and legislative bodies when defining policies and benchmarks for air quality and for the control of air pollutants (4).
They led to a revision of the previously recommended values, with reductions in guide values relevant for all pollutants, in particular for the annual value of PM2,5 and NO2. For example, in 2005 the highest recommended annual average emission level for PM2.5 was 10 μg/m3; the 2021 revision halves this figure to just 5 μg/m3. The recommended annual average emission level for PM10 in 2021 is 15 μg/m3 (it was 20 μg/m3 in 2005). Daily exposure levels are also lowered. For the nitrogen dioxide, WHO guidelines have been drastically revised from 40 to 10 μg/m3 on average per year.
Sabrina Bergamini
1. Air quality constantly improving but EU standards still not fully met, latest EEA data analysis shows
https://www.eea.europa.eu/en/newsroom/news/air-pollution-standards-still-not-fully-met-across-europe
2. Air quality status report 2025
https://www.eea.europa.eu/en/analysis/publications/air-quality-status-report-2025
3. WHO global air quality guidelines: particulate matter (PM2.5 and PM10), ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide
https://iris.who.int/handle/10665/345329
4. Air quality: the new WHO guidelines. https://www.epicentro.iss.it/ambiente/qualita-aria-linee-guida-oms-2021